This invention relates to thread cutters for sewing machines of the type manually operated by pulling the thread to be cut against an exposed cutting edge. Various devices have been utilized as thread cutters which attach conveniently to the sewing machine. Such devices usually employ a knife member having either a straight or arcuate cutting edge. The member is attached to the presser bar, or some other part of the sewing machine at a convenient height and position. Examples of such devices are disclosed in U.S. Pat. No. 127,054, May 21, 1872, Harris and U.S. Pat. No. 332,759, Dec. 27, 1885, Spees.
Another line of development has produced cutters which are integral to an existing part of the sewing machine such as the presser foot or presser bar. Examples of these devices are disclosed in U.S. Pat. No. 280,970, July 10, 1883, Staples and U.S. Pat. No. 2,781,012, Feb. 12, 1957, Kuhar. Both of these patents disclose cutters which are formed by a slot machined in the presser foot or bar so that a sharp edge is presented to the operator.
All of the above devices require that the thread to be cut be presented to the cutter from one or two limited directions, thus effecting convenience. Additionally, the cutters of Harris and Spees are arranged so that their cutting edges are relatively unprotected, increasing the risk of injury to the operator.
The present invention overcomes these disadvantages through the use of a novel but simple device.